Wave energy always seemed like one of those technologies that sounded cool but was always 10 years away from a practical implementation. I think the massive rise in solar over the past decade or so is partly to blame for this as whilst it has its disadvantages it’s readily available and at prices that make even the smallest installations worthwhile. However it seems that whilst the world may have turned its eyes elsewhere an Australian company, Carnegie Wave Energy, has been busy working away in the background on developing their CETO technology that can provide a peak power output of some 240KW. In fact they’ve just installed their first system here in Australia and connected it to the grid to provide power to Western Australia.
The way these pods work is quite fascinating as much of the technology they use has been adapted from offshore oil rigs and drill platforms. The buoy sits a couple meters under the surface and is anchored to the sea bed via a flexible tether. As the waves move past them it pulls on the cable, driving an attached pump that creates high pressure sea water. This is then fed up through a pipe to an onshore facility where it can be used to drive a turbine or a desalination plant. These CETO pods also have some other cool technology in them to be able to cope for rough sea conditions, allowing them to shed energy so that the pumps aren’t overdriven or undue stress is put on the tether.
What’s really impressive however are the power generation figures that they’re quoting for the current systems. The current CETO 5 pod that they’ve been running for some 2000 hours has a peak generation capacity of about 240KW which is incredibly impressive especially when you consider what comparable renewable energy sources require to deliver that. Their next implementation is looking to quadruple that, putting their CETO 6 pod in the 1MW range. Considering that this is a prototype slated to cost about $32 million total that’s not too far off how much other renewables would cost to get to that capacity so it’s definitely an avenue worth investigating.
I’m very interested to see where Carnegie Wave Energy takes this idea as it looks like there’s a lot of potential in this technology they’re developing. With offshore wind always meeting resistance from NIMBYs and those who think they ruin the view something like this has a lot of potential to work in places where the other alternatives aren’t tenable. That, coupled with the fact that they can be run as either power generation units or desalination plants, means that the technology has a very large potential market. Of course the final factor that will make or break the technology is the total installed cost per KW however the numbers are already looking pretty good in that regard so I’m sure we’ll be seeing more of these CETOs soon.
